parallel.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE suite SYSTEM "http://testng.org/testng-1.0.dtd">
<suite name="BDD Test Suite" verbose="1" parallel="tests"
       thread-count="2">
    <test name="Galaxy" annotations="JDK"
          preserve-order="true">
        <parameter name="deviceName" value="Galaxy.*"/>
        <parameter name="platformVersion" value="11"/>
        <parameter name="platformName" value="Android"/>
        <classes>
            <class name="MyRunner.TestRunner"/>
        </classes>
    </test> <!-- Test -->
    <test name="OnePlus" annotations="JDK"
          preserve-order="true">
        <parameter name="deviceName" value="Pixel.*"/>
        <parameter name="platformVersion" value="12"/>
        <parameter name="platformName" value="Android"/>
        <classes>
            <class name="MyRunner.TestRunner"/>
        </classes>
    </test> <!-- Test -->

</suite>